1. Field of the Invention
This invention relates to a tamper-resistant closure for use with container necks characterized in that the neck is sealed with a foil disc.
2. Description of Related Art
Reference is made to U.S. Pat. No. 4,484,687 and the references cited therein.
Foil liner seals have been used to close the necks of containers as a means to assist in detecting tampering with the contents of the container. Such commercially available seals are applied to the container neck and are caused to adhere thereto by induction heating or other means. In a preferred embodiment of this invention, such commercially available foil liner seals are used. To facilitate installation on the container neck, the seal is initially inserted into the cap and remains therein until the container is opened by the consumer. The underside of the foil seal preferrably has an adhesive so that, after the cap has been applied to the neck, the adhesive comes into intimate contact with the neck. Induction heating, or other means, then causes the foil seal and adhesive to adhere to the neck finish.
One feature of the present invention is the formation of a groove on the interior of the cap skirt into which the margin of the foil seal snaps and remains until the cap is removed from the container neck. The groove holds the foil liner seal in place prior to the cap being applied to the container.
Another feature of the invention is the provision of a foil tab integral with the foil seal which may be gripped by the consumer to assist in pulling the foil off the container neck finish. Preferably, this tab is folded over the seal disc and nests between the foil and the underside of the top disc of the cap. To use the tab after the cap has been removed, the consumer may insert a fingernail or other instrument under the folded over tab and pull it to upright or upward extending position.
Another feature of the present invention is the fact that the cap and container neck have cooperating locking means to hold the cap securely in place until the lower portion thereof may be torn off. Tearing the skirt gives visual evidence of tampering. The interlocking means are preferably beads and the beads may be either continuous, as illustrated in FIG. 1 of the drawings, or may be interrupted as is shown in FIG. 6 or interrupted in other patterns.
Another anti-tamper-resistant feature of the present invention is the provision of a flange on the top of the cap which may be gripped by the consumer to remove the cap after the lower part of the skirt has been torn away. However, until the lower portion of the skirt has been torn off and a portion of the locking means thereby removed, the flange cannot be used by a dishonest consumer to remove the cap. Various shapes of flanges may be used, as hereinafter described.
Still another tamper-resistant feature is the use of a container neck provided with an outwardly extending shoulder against which the lower edge of the cap skirt tightly abuts to make it difficult, if not impossible, to dig one's fingernails under the skirt to pry up the cap off of the neck. The shoulder may be formed with protrusions to frustrate insertion of an implement under the skirt edge.
Other objects of the present invention will become apparent upon reading the following specification and referring to the accompanying drawing in which similar characters of reference represent corresponding parts in each of the several views.